JPS63317980A - Optical disk device - Google Patents

Abstract

PURPOSE:To improve the processing speed at readout by writing a special pattern to a data part shorter than a conventional data if an address part has a defect. CONSTITUTION:When an address detection error detection circuit 12 detects a defective address part, a special pattern generator 6 is started by a signal 111 and generates a special pattern shorter than a conventional data as a signal 107. A selector circuit 9 is thrown from the position of a modulation circuit 5 into the circuit 6 by a defect Add Det signal 120 from the circuit 12 and the special pattern is written in the data part. On the other hand, in reading the sector, positioning is applied before several sectors and the data from an alternate sector is read if required. The write to all data write instructions is guaranteed by the operation and the discrimination of unwritten sector at readout is quickened.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The non-explosion F3A relates to an optical disk device for data recording/reproduction that takes into account processing in the event of a media defect.

(Prior art) In conventional original disk devices, if there is a defect in the address part of a sector, or if there are defects in the address part of two consecutive sectors, the data is not written or a defective flag is flagged. Processing such as writing flags was performed.

(Problems to be Solved by the Invention) In the above-mentioned conventional source disk device, data reliability is lost due to data positioning variations in response to a defect in the address section, and there is a risk that the address section or data section of the next sector will be written out. Therefore, that sector was left unwritten and data was written to an alternative sector.

This method first searches all alternative sectors for unwritten sectors when reproducing data.

This caused a decrease in processing efficiency because it became clear that data had not been written. Furthermore, the method of writing a flag of several bytes in response to a defect in the address section has the problem of erroneous detection due to check end variations due to increased positioning errors in the address section.

An object of the present invention is to avoid using the conventional method of replacing the sector with an unwritten alternative sector or writing a flag in the flag area in response to a defect in the address area. By writing a special pattern shorter than normal data in a data section with extra space and then performing alternative sector processing, it is possible to indicate an address defect and to reread at high speed without having to overwrite the previous or subsequent address section. The object of the present invention is to provide an optical disc device with the following features.

(Means for Solving the Problems) In order to achieve all of the above objects, an optical disk device according to the present invention has an address section and a data section in each sector of the original disk medium, and writes and reads data to and from the data section. In an optical disk device that performs replacement sector processing when there is a defect in the address section, there is an address error detection circuit that detects an abnormality in the address section, and a special detection circuit that is activated by the address error detection of the address error detection circuit and generates a special pattern. A pattern generation circuit, a selector circuit that switches the data of the modulation circuit to the special pattern according to the write gate signal from the address error detection circuit and sends it to the write head, and a special pattern detection circuit are provided. By writing a pattern, ffi & indicates that the sector is defective in the address section, and by detecting a special pattern on the data section, it is recognized that the sector is defective in the address section.

(Example) Hereinafter, the present invention will be explained in more detail with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of an optical disc device according to the present invention.

When the host interface control circuit 1 receives a write command from a host system (not shown) through the signal 101, it transfers the command to the microprocessor 4 through the data bus 105'i.

The microprocessor 4 sends a data transfer request to the host system, and when the write data is sent, the microprocessor 4
The write data is taken into the data buffer 2 throughout. The captured data is sent to the error correction circuit 3 via the bus 103. The microprocessor 4 receives the information in the address part from the address detection circuit 12, and sends the information to the selector 9 and the read/write circuit I in order to write the data to the designated sector through the entire modulation circuit 5 onto the disk medium.
I! ! Operate r11.

Next, when receiving a read command, the microprocessor 4 similarly positions the microprocessor 4 to the specified sector using the address detection circuit 12 and transfers the data to the demodulation circuit 7 and the error correction circuit 3.

After the read data is corrected by the error correction circuit 3, it is sent to the host interface control circuit FNr via the data buffer 2.
1 is forwarded to the host system'\.

Next, referring to FIGS. 1 and 2, the operation in the case of an abnormality in the address section will be described. FIG. 2 is a time chart for explaining the operation of FIG. 1. Of the signal divisions in the time chart in Figure 2, division A is normal, division B is a faulty address and the rotation speed is slow, and division C is
1 and 2 respectively show cases where there is a bad sector and the rotation speed is high. Note that B and C are operation examples of the conventional device.

Sector mark pulse (SMP) signal 1 [IL-11!
- Occurs immediately after the lid mark is detected, but if the address part is defective, the SMP interpolation pulse W! shown in FIG. 1 is generated! Generated by r11. This is due to the rotational fluctuation of the disk.
The occurrence position changes as shown by ■ in B and ■ in C in the figure. For this reason, in the conventional device, there is a possibility that the write gate is opened and the write data overlaps the address portion as shown at point 0.0.

The device of the present invention does not operate as described above.

When the address error detection circuit 12 detects a defective address part, the special pattern generator 6 is activated by the signal 111 during writing.
is activated and transmits the special pattern shown in FIG.
Occurs as 7.

On the other hand, the selector circuit 9 is switched from the modulation circuit 5 to the special pattern generation port W66@ by the defective AddDet signal 120 from the address error detection circuit 12. This causes the special pattern to be written into the data section.

The second chart section shows the signal state at this time. Although the SMP signal is not described in Section 9, it is generated by the SMP interpolation circuit 11, and a special pattern is written in the data section at a certain position for this SMP signal instead of the data from the modulation circuit 5. . As mentioned above, in the past, the SMP signal's generation position changed due to fluctuations in disk rotation, and there was a possibility that the data part overlapped with the address part, but since the special pattern is several tens of bytes shorter than normal data, this caused the address part to change. No overrides will occur.

On the other hand, when reading this sector, positioning is performed several sectors in advance, and the special pattern detection circuit 8 detects the position.
Read data from the alternate sector if necessary.

The above operation guarantees writing for almost all data write commands, and enables quick determination of unwritten sectors during reading.

(Effects of the Invention) As explained above, in the present invention, when there is a defect in the address field, by writing a special pattern in the data field several hundred bytes shorter than the normal data, the defective address can be addressed without completely damaging the address field. It is possible to leave data as a writing source mark in the memory, and there is an effect that the processing speed at the time of reading can be completely improved.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the original disk device according to the present invention, FIG. 2 is a time chart for explaining the operation of FIG. 1, and FIG. 3 is a diagram showing an example of a special pattern. 1...Host interface control circuit 2...Data buffer times! 3...Error correction circuit 4...Microprocessor 5...Modulation circuit 6...Special pattern generation circuit 7...Demodulation circuit 8...Special pattern detection circuit 9...Selector circuit 10...・R/W circuit 11・
...Sector pulse interpolation circuit 12...Address detection error detection circuit 201...Address section 202...Data section 203.205...
・Defective address section 204...data section

Claims (1)

[Claims] Each sector of an optical disk medium has an address section and a data section, and when writing and reading are performed on the data section, an abnormality in the address section is detected in an optical disk device that performs replacement sector processing, etc. if there is a defect in the address. an address error detection circuit; a special pattern generation circuit that is activated by the address error detection of the address error detection circuit and generates a special pattern; and a write gate signal from the address error detection circuit to convert the data of the modulation circuit into the special pattern. A selector circuit and a special pattern detection circuit are provided to switch to the read/write head, and write a special pattern in the data area to indicate that the sector has a defect in the address area. An optical disc device characterized in that it recognizes that an address section is a defective sector by detecting a pattern.